Apple has embedded a special message to hackers in the latest version of its operating system in an effort to stop the platform being ported to non-Apple computers. 

Developers have been trying to break into Apple's OS X ever since the company released a version of the software that runs on Intel processors. Previous versions ran only on Power processors made by IBM and Freescale.

A limited group of developers was granted access to the Intel version of the software last summer, and the code was released to the public in January when Apple started shipping its Intel-powered iMacs. 

A hacker working on porting OS X to non-Mac systems encountered the poem, which has been circulating on Mac forums:

Your karma check for today:

There once was a user that whined
His existing OS was so blind
He'd do better to pirate
An OS that ran great
But found his hardware declined

Please don't steal Mac OS!
Really, that's way uncool

© Apple Computer Inc

An Apple spokesman confirmed to vnunet.com that the poem is embedded in the software. "Hopefully it, and many other legal warnings, will remind people that they should not steal Mac OS X," he said.

Apple is also believed to be using a special security chip called the Trusted Platform Module to limit the OS X operating system to Mac computers.

The chip has a unique identifier that allows the software to determine whether it is running on Apple or non-Apple hardware.

But software could emulate such a chip, spoofing the application into believing that the chip is present when it is not.

Developers have already succeeded in running the developer version of OS X for Intel on non-Apple hardware, and it is generally assumed to be only a matter of time before they succeed in doing the same for the consumer version.